124655-09-0Relevant articles and documents
STEREOSELECTIVE REDUCTION OF β,δ-DIKETO ESTERS DERIVED FROM TARTARIC ACID. A FACILE ROUTE TO OPTICALLY ACTIVE 6-OXO-3,5-syn-ISOPROPYLIDENEDIOXYHEXANOATE, A VERSATILE SYNTHETIC INTERMEDIATE OF ARTIFICIAL HMG Co-A REDUCTASE INHIBITORS.
Minami, Tatsuya,Takahashi, Kyoko,Hiyama, Tamejiro
, p. 513 - 516 (1993)
Reduction of β,δ-diketo esters derived from tartaric acid with HAl(i-Bu)2 gave stereoselectively β-hydroxy-δ-keto esters which were reduced with NaBH4 and Et2BOMe to β,δ-syn-dihydroxy esters.This strategy was successfully applied to the synthesis of t-butyl (3R,5S)-6-oxo-3,5-isopropylidenedioxyhexanoate starting from D-tartrate.
Preparation method of rosuvastatin calcium intermediate
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Paragraph 0040-0047, (2021/11/21)
Preparation method of rosuvastatin calcium intermediateTo the preparation method of the compound CL - 9, the compound CL - 8 is subjected to organic alkali treatment to obtain the compound CL - 9. The compound CL - 9 prepared through the route has the advantages of high yield, high purity, controllable impurities, suitability for industrial production and the like.
Efficient and Practical Deacylation Reaction System in a Continuous Packed-Bed Reactor
Yasukouchi, Hiroaki,Machida, Koji,Nishiyama, Akira,Mitsuda, Masaru
supporting information, p. 654 - 659 (2019/04/01)
The ester deacylation reaction is widely applied in organic synthesis for preparing desired hydroxy compounds, as the acyl group is often used for protecting the hydroxyl group. This reaction is usually performed by acid, base, or enzyme catalysts, which have to be removed by complicated workups such as extraction or filtration in batch mode. Therefore, a simple deacylation process is desirable to improve productivity, especially at the industrial scale. In this work, we established an efficient and practical packed-bed reactor system for undertaking the deacylation reaction using an anion-exchange resin that provides a simple process compared with batch processing. We also demonstrated that this technique is applicable to the preparation of a wide variety of desired pharmaceutical intermediates containing hydroxy groups in good to excellent yields.
Preparation method of rosuvastatin calcium medicine intermediate
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Paragraph 0029; 0042; 0045; 0050; 0051; 0056, (2018/11/03)
The invention belongs to the technical field of medicine chemicals, and particularly relates to a preparation method of a rosuvastatin calcium medicine intermediate. The preparation method comprises the following steps of using monochloroacetaldehyde as the raw material; substituting, condensing, and chirally catalyzing, so as to prepare a compound V; protecting by 2,2-dimethoxypropane, and debenzylating, so as to obtain a target compound I. The preparation method has the advantages that the raw materials are easy to obtain; (S)-5-benzyl-2,2,3-trimethyl-4-thioketone is used as a catalyst for stereo selective reduction, the reaction conditions are mild, the yield rate is higher, and the industrialization production of the component I is easy.